Allos Therapeutics, Inc. (Nasdaq: ALTH) announced today that the Agreement and Plan of Merger and Reorganization (“the Merger Agreement”) entered into by and among Allos, AMAG and Alamo Acquisition Sub, Inc. on July 19, 2011, as amended on August 8, 2011, has been terminated. The Merger Agreement was terminated following the October 21, 2011, special meeting of AMAG stockholders at which AMAG's stockholders voted against the issuance of shares of AMAG common stock to Allos’ stockholders in the proposed merger. Separately, a majority of Allos’ stockholders voted in favor of the adoption of the Merger Agreement at a special meeting of Allos stockholders also held on October 21, 2011. “The Board and shareholders of Allos supported the proposed merger with AMAG based on the strategic rationale, anticipated operating synergies and potential for future growth of the core brands. With the termination of the merger agreement, we will remain focused on growing U.S. sales of FOLOTYN for relapsed or refractory PTCL, as well as pursuing future label expansion opportunities in T-cell lymphoma and regulatory approval in the EU, which may occur in early 2012,” commented Paul L. Berns, President and Chief Executive Officer of Allos. “We ended the third quarter with no debt and $100.4 million in cash and investments, which based on our historical sales levels for the first nine months of 2011, we believe will be sufficient to fund our operations through early 2014. Achievement of growth in U.S. sales and/or potential milestone payments and royalties associated with regulatory approval of FOLOTYN in the EU would further extend our cash resources.” Conference Call Information Allos will host a conference call to review its third quarter 2011 financial results on November 3, 2011, at 8:30 a.m. ET. Participants can access the call at 1-877-941-2927 (U.S.) or +480-629-9725 (Canada and international). To access the live audio webcast or the subsequent archived recording, visit the “Investors - Presentations and Events” section of the Allos website at www.allos.com. Webcast and telephone replays of the conference call will be available approximately two hours after the completion of the call. Callers can access the replay by dialing 800-406-7325 (domestic) or 303-590-3030 (international). The passcode is 4438057#. The webcast will be recorded and available for replay on Allos’ website until November 17, 2011. About Allos Therapeutics Allos Therapeutics, Inc. (Nasdaq: ALTH) is a biopharmaceutical company committed to the development and commercialization of innovative anti-cancer therapeutics. Allos is currently focused on the development and commercialization of FOLOTYN ® (pralatrexate injection), a folate analogue metabolic inhibitor. FOLOTYN is approved in the U.S. for the treatment of patients with relapsed or refractory PTCL. For additional information, please visit www.allos.com. IMPORTANT SAFETY INFORMATION Warnings and Precautions FOLOTYN may suppress bone marrow function, manifested by thrombocytopenia, neutropenia, and anemia. Monitor blood counts and omit or modify dose for hematologic toxicities.